设A是Banach代数,M是Banach A模,从A^n到M的n元线性映射f：A^n→M称为n-上循环是指任给x1,…,xn＋1∈A都有x1f（x1,…,xn＋1）＋（-1）^n＋1f（x1,…,xn......

A square root functional equation on positive cones of C*-algebras is introduced and its solution and Hyers-Ulam-Rassias......